I agree with @reaperhulk :-)
On Apr 19, 2014 10:14 AM, "Paul Kehrer" <notifications@github.com> wrote:

> In cryptography/hazmat/backends/openssl/backend.py:
>
> > @@ -469,6 +470,13 @@ def generate_dsa_private_key(self, parameters):
> >              y=self._bn_to_int(ctx.pub_key)
> >          )
> >
> > +    def cmac_algorithm_supported(self, algorithm):
> > +        return (backend._lib.Cryptography_HAS_CMAC == 1
> > +                and backend.cipher_supported(algorithm, CBC(0)))
>
> I still don't like passing 0 to this constructor. I realize we have no
> intention of using the data inside but it feels wrong to do this.
>
> —
> Reply to this email directly or view it on GitHub<https://github.com/pyca/cryptography/pull/931/files#r11793905>
> .
>